Fastener



v I 1,557,381 t 13 1 e. SUNDBACK FASTENER Filed Jan. 8, 1923 mv TOR 4 g JBY/ ATTORNEY the type described in 'my nearly identical in'fit, as in said patent,-

Patented Oct. 13, 1925.

cinnon sonnnncx, or MEADVILLE,

PENNSYLVANIA, Assrenon ro- HOOKLESS FASTENER comr'nmr, A conrom'rron or rnmzsYLvANm.

' EASTENER...

I Application filed. January 8, 1923. Serial No, 611,211.

To all whom it may concern:

Be itknown that I, GIDEON SUNDBACK, a subject of the King of Sweden, and resident of- Meadville, in the county of Oraw-' 5 fordand State of Pennsylvania, have invented certain new and useful Improvements in Fasteners, of which the following is v a specification.

This invention relates to fasteners of Patent No. 1,243,458, October 16,1917, which shows a plurality of interlocking members disposed along the edges of stringers on opposite sides of a slit where the interlocking mem- 15 bers are controlled by a-slidable operating device. An objectof this invention is to provide increased flexibility and reliability, reduced cost ofproduction, and longer life of. the fastener.

According to this invention, a clearance is provided between the projection of one interlocking. member and the walls of therecess in its cooperatingmember so located relatively to the stringers and'the heads and recesses as to adapt this fastener for use with washable articles such as overalls,

I childrens clothing, etc., where diificulty has been encountered due to shrinkage of the tape stringers, or the fabric to which attached. This clearance results from a different contour of the sockets and projections shown in said patent and enables quite wide variations in stringer length and member v spacing to exist without causing the memhers to jam, or. to become so loose as not-to stay interlocked. Also, where the members tend "to jam, excessive wear is caused on the slider, or even distortion suflicient'to render a new one necessary. Since the projectionsand-cooperating sockets are not so the dies and punches used in makin the members need 'not be of such high'precision, and may, be used for a longer time when '45 worn from their original contounbecause-of the greater clearances permitted by-this in vention, thus cheapening thetool and labor ..cost of production.

Referring to the drawings:

- Fig. 1 is an enlarged view of the improvedlfastener, mounted on cords 6 sewed to stringers 26.

F-Fig. 2 is a section on the line 2w-2a of 1g. 1. i v

Fig. 3 illustratesthe die and punch used in forming the projection and recess in each interlocking member.

Figure 1 shows a plurality of interlocking members 7 secured to the stringers 26 along opposite sides of an opening and adapted to be controlled by the slidable operating device 8 in a similar manner to that described in my Patent No. 1,243,458, October 16, 1917. Each interlocking member 7 is provided with a projection 3 on oneside thereof and an aligned recess 2 on the opposite side for cooperation with the projection of the adjacent interlocking member.

These projections and recesses are trans-' versely elongated as shown in the previous patent referred to, and the operation of these members is similar to that described in the patent. So also each stringer 26 may be provided with an end member 10 for limiting the movement of the slider 8 in closing the slit and the opposite ends of the stringers may be permanently secured by a member 9 as is also described in that patent.

tener to be applied towash able goods which are likely to shrink. When the interlocking members closely fit within one another, as indicated in the prior patent referred to, shrinkage of the material results in bringing the interlocking members so close together .as 'to be incapable of properly engaging, or ifunuSuaI means are taken to move the slider, the interlocking members will be moved out of their positions on the stringers, which invariably makes the fastener useless for future service. The amount of separation between adjacent interlocking members must bear a relation to the height of the projection and must be less than one-half the height of such projection. In other words, the distance from the top 15 of a projection to the bottom 16 of its cooperating socket, when in normal position, must be greater than the separation of the connecting members, so that if one of the interlocking members be moved longitudinally into contact with the adjacent member on one side, the adjacent interlocking member on the opposite side must still be in cooperation in order to prevent the fastener from becoming open. Both the sockets and projections in this invention are made tapered in order to'better provide guiding surfaces as the slider brings the members into interlocked position, and as described in Patent No. 1,243,458. VJith tapered surfaces for the recesses and projections a certain amount of lateral clearance is necessary as shown in Figure 1 in order to allow the desired longitudinal movement with shrinkage and stretching of the washable goods. In- Fig. 2 it will be observed the recesses and projections are transversely elongated, and with slightly less clearance between the members in the transverse direction shown in this figure than is the case in the plan View shown in Fig. 1. In Fig. 1 it will be noted the outer surface '19 of each projection is substantiallvcontinuous with the outer surface 20 of the interlocking member, while in Fig. 2 the transverse section shows that in this direction the surface 17 of the projection is not continuous but forms an angle with the surface 18 of the interlocking member. The clearance shown in Fig. 2 must not be too large or the fastener might be opened by moving one of the interlocking members to the right or left of its position shown in this figure, when these members might become unlocked if the clearance is not within the permissible limits. Any form of stringers 26 may be used, either the kind described in my Patent No. 1,243,458, or that of my Patent N 0. 1,322,650 of November 25-, 1919.

When the interior surface 1 of the slider 8 became worn beyond a small amount, the interlocking members of the previous patent would not necessarily be brought into engagement and properly interlocked. This wear takes place in all fasteners and the length of serviceability in this respect varies with therelation between the width of the channel in the slider, the width of the fastener, and the clearance between projections and recesses. With the lateral clearance lndicated between projections and recesses the fastener will continue serviceable until such wear results that the outside edge 13 of the recess will not move down over the inside edge 14 of a projection.-

Fig. 3 shows how the punch 5 operates on the connecting member7 in the die 4 to form the recess and projection in one operation. Since the recess is larger than the projection the same care need not be exercised in having the recess and projection of precisely the right size, and, therefore, the punch 5 and the die 4 may be used for a longer time after they have become worn more than was previously permissible without the clearance. Prolonged useof the dies and punches obviously results in a cheapened cost of production. As shown in the drawing the sides of the recess and projection are tapered and form an angle of about 33 with the vertical. Or, more precisely, the surfaces 17, 19 and 20 are inclined at substantially 33 with the vertical, while the surface 21 is somewhat steeper, being at an angle of about 25, and the surface 18 is more steep, being at .an angle of about 12 with the vertical. It will be understood that these surfaces are rounded and that no edge or sharp line of demarkation exists between the surfaces 17, 19 and 21. Being rounded the intermediate surfaces gradually change their inclination.

In addition to the foregoing needs for lateral clearance, such is especially necessary when the interlocking membersare of varying widths, as otherwise these members could not be readily engaged and disengaged. The variations in width of the interlocking members may result from a number of causes, such as'the wearing of rolls in making the wire in the formation of these interlocking members, the wearing of the cutting die and knives in the slicing machine for making these members, the adjustments and irregularities in the forming machines, and the setting of the tools which form the projections and recesses in the interlocking members. Also the sliders may vary in internal width at the time of production as well as due to wear.

i Among the advantages of this invention maybe enumerated the greater flexibility of the fastening in all directions when provided with the clearance described without lessening the holding power. Greater wear being possible on the internal surface of the slider makes for longer life and ability of this fastener to stand up under more prolonged usage. The field of use of this-invention is enlarged because applicable to wash goods wherein shrinkage may occur. The reduced cost of production through the necessity of grinding the punches and dies less frequently is another advantage. This fastener may be used on curved or straight slits, with any type slider, and locking alinement with said projection, the recess being enough larger than the projection to permit a lateral movement between the in-' terlocked members.

2. In a fastener, an interlocking member having a rounded recess on one. side, and a I rounded projection on the opposite side continuous with the outer edge of said member, said recess being larger than said projection to provide both lateral and transverse clearance, the lateral clearance being greater than the transverse clearance.

3. A plurality of interlocking members for an opening controlled by a slider, each member having a tapered projection on one side and a larger tapered recess on the'opposite side, said members being arranged along the opposite edges of said opening to permit shrinkage of the material containing said opening and permit said members to be moved together longitudinally while not interlocked without interfering with the ability of said members to be controlled by the slider.

4:. A fastening means for the opposite edges of a slit material adapted to be progressively controlled by a slider and comprising a plurality of similar interlocking members, each comprising a tapered projection on one side and an aligned tapered recess on the opposite side for. cooperation with the complementary, portions of similar members, the projection of each member being smaller than its recess, whereby each projection is adapted to have a clearance on all sides thereof while interlocked.

I 5. The combination with a plurality of similar interlockin members arranged along the opposite sides ofan opening and each provided with a ta ered recess and projection, of a slider or progressively controlling said members, the adjacent interlocking members being spaced apart longitudinally to permit of lateral flexibility and longitudinal movement without affecting the facility of engagement.

6. A plurality of interlocking members adapted to be controlled by a slider,each member being provided with a projection on one side and a recess on the opposite side,

the adjacent interlocking members being spaced apart when interlocked and the projections and recesses being tapered and proportioned to insure transverse flexibility of the fastener while interlocked.

7. YA plurality of interlocking members adapted to be actuated by a slider, each member being'provided with a projection on site side larger than said projection to permit clearance between the recess and the projection of an adjacent member cooperatmg therewith, both the projection and recess having tapered sides forming an angle of aboutv33 with the vertical.

8. In a fastener, an interlocking member having a transversely elongated recess on one side and an alined transversely elongated tapered projection on the opposite side smaller than said recess in order to provide lateral clearance.

9. The combination with a plurality of interlocking members arranged along the opposite edges "of stringers, of a slider adapted to control said members, each member having a recessed portion on one side i and an aligned pro ect on on the opposite side, both the recess and projection being tapered, the sides of the projection and the outer sidessof the interlocking member on a transverse section through the recess and projection and normal to the stringers being at an angle to one another and with the outer sides of the interlocking member tapered less than the sides of the projection.

10. The combination with a plurality of interlocking members arranged along the opposite edges of an opening, of a slider adapted to control said members, each member being provided with a transversely elongated and tapered recess and projec-' tion, one on one-side and the other on the opposite side, said members being spaced apart longitudinally to permit shrinkage and stretching of the material to which they are applied, the spacing between said members being less than half the height of the projection on each member.

11. In a fastener, a plurality of interlocking members arranged along flexible stringers on opposite sides of an opening and adapted to be controlled by a slidable operating device, each member having a transversely elongated recess on one side and a transversely elongated projection tapered on the opposite side the adjacent members on the same side of the openings being disconnected except. for said stringers one side and an aligned recess on the oppoand spaced apart substantially more than the being both inclined, with'said sides of the projection being inclined a greater amount than the sides of the member,

13. An interlocking member adapted to 5 be secured to a stringer and provided with a projection on one side and a recess on the opposite side for cooperation with similar members, the sides of said member and projection taken on a transverse section 1 through the recess and projection, at right angles to the plane of the stringer, being both inclined, with said sides of the projection forming an angle of about 33 with the vertical, while the sides of said member on the same transverse section form an angle of substantially 12 with the vertical.

Signed at M'eadville, in the county of Crawford and State of Pennsylvania, this 2nd day of January A. D. 1923.

GIDEON SUN DBACK. 

